There have been various tread locking devices disclosed in the prior art.
Examples of the prior art are U.S. Pat. Nos.: 4,246,947 to Ewing, dated Jan. 27, 1981; 2,152,684 to E. A. Grange, dated Apr. 4, 1939; 2,152,685 to E. A. Grange, dated Apr. 4, 1939; 1,943,881 to R. R. Ware, dated Jan. 16, 1934; 1,0577462 to F. W. Kremer, dated Apr. 1, 1913; 848,745 to J. E. Hopkinson, dated Apr. 2, 1907; 824,345 to M. A. Elliott, dated Jun. 26, 1906; 813,423 to E. Hill, dated Feb. 27, 1906; 771,947 to J. A. Swinehart, dated Oct. 11, 1904.
The previous prior art affords only marginal performance under limited conditions. The average polyurethane wheels are harder than rubber but still resillient while providing a co-efficient of friction less than rubber for traction, but are higher in load rating when compared to the rubber wheels. The present invention using Isoplast.sup.R 202 and Victrex Peek.sup.R is far superior in that basically, its load rating is many times higher than the best polyurethane wheels, which also benefits from a newly structured design with additional parts providing the best tread locking possible along with the highest load rating possible, for a polyurethane wheel product and another feature is that a new type of wheel is created for the automotive and materials handling industry; namely, the best wheel, roller and track tread used for all types of applications wherever a wheel, roller, or track tread is needed regardless of size or type of use, an example is the best pallet jack load wheel to date, with a sufficient safety factor of at least 2 and as high as 4 for the load rating, in the polyurethane class of wheels used on electric pallet jack machines. This safety factor enables the driven electric pallet jack machines to carry their rated load, not a partial load as for conventional load wheels. The present invention operates under all weather conditions. The present invention can be applied to all types of wheels, industrial, automotive, and rollers for all types of loads heavy and light as well with low height from bottom of vehicle to floor for wheel usage. It is the first wheel and roller assembly of its kind to match the weight load rating (tire load rating) of a conventional heavy truck class rating; example: a conventional rubber tire used for Interstate use, conventional road use, and off the road use, etc.
The wheel assembly is also highly resistant to acids, fuels such as gasoline, diesel fuel, other liquid fuels, and other chemicals; caustic alkali materials, caustic acids, sulfuric acids, hydrochloric acids, chemical solvents, etc. This is achieved through the use of Isoplast.sup.R grade 202 or Victrex Peek.sup.R material molded onto the wheel tread locking hub.
There is also an alternate use of the Isoplast.sup.R 202 and Victrex Peek.sup.R as an inner support liner located inside between the sidewalls and against the inner bottom of a conventional tire, either tubeless or conventional tube type for the automotive field. This will afford the conventional automotive tires puncture proof operation and extra capacity for safety on the sidewalls where blowouts can occur. The inner liner prevents this with tube type or without an inner tube for tubeless type automotive tires. The automotive rubber tire can either be mechanically fastened or molded around the Isoplast.sup.R or Victrex Peek.sup.R inner liner. This is the product for the future available today.